Inositol 1,3,4,5-tetrakisphosphate increases the duration of the inositol 1,4,5-trisphosphate-mediated Ca2+ transient.
Inositol 1,3,4,5-tetrakisphosphate increases the duration of the inositol 1,4,5-trisphosphate-mediated Ca2+ transient.
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肌醇 1,3,4,5-四磷酸增加了肌醇 1,4,5-三磷酸介导的 Ca2 瞬变的持续时间。
DOI：
10.1016/0014-5793(87)81203-6
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发表时间：
1987
期刊：
影响因子：
3.5
通讯作者：
Williamson,JR
中科院分区：
文献类型：
--
作者：
Joseph,SK;Hansen,CA;Williamson,JR
已在透化肝细胞中检查了Ins 1，3，4，5-P4对Ins 1，4，5-P产生的细胞内Ca 2+动员的影响。Ins 1，3，4，5-P4不影响Ins 1，4，5-P3介导的Ca 2+释放的幅度，但确实抑制释放的Ca 2+重新积聚回细胞内储存。Ins 1，3，4-P3没有模仿这种效应。在肝细胞中，响应的再摄取阶段由Ins 1，4，5-P3水解引起。使用标记底物的测量表明，Ins 1，3，4，5-P4抑制Ins 1，4，5-P3的水解，反之亦然。由于去除Ins 1，4，5-P3和Ins 1，3，4，5-P4上的5-磷酸盐是处理这两种化合物的共同步骤，因此建议Ins 1，3，4，5-P4的生物学效应之一可能是减缓Ins 1，4，5-P3的水解，从而延长Ca 2+瞬变的持续时间。
The effect of Ins 1,3,4,5‐P4on the intracellular Ca2+mobilization produced by Ins 1,4,5‐P, has been examined in permeabilized hepatocytes. Ins 1,3,4,5‐P4did not affect the magnitude of the Ins 1,4,5‐P3‐mediated Ca2+release but did inhibit re‐accumulation of the released Ca2+back into intracellular stores. This effect was not mimicked by Ins 1,3,4‐P3. In hepatocytes, the re‐uptake phase of the response results from Ins 1,4,5‐P3hydrolysis. Measurements using labeled substrates indicate that Ins 1,3,4,5‐P4inhibits the hydrolysis of Ins 1,4,5‐P3and vice versa. Since the removal of the 5‐phosphate on Ins 1,4,5‐P3and Ins 1,3,4,5‐P4is a common step in the disposal of both compounds, it is suggested that one of the biological effects of Ins 1,3,4,5‐P4may be to slow hydrolysis of Ins 1,4,5‐P3and thereby prolong the duration of a Ca2+transient.